722
FXUS65 KBYZ 021855
AFDBYZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
1255 PM MDT WED SEP 2 2026
KEY MESSAGES
- SHOWERS AND THUNDERSTORMS POSSIBLE TODAY; A STORM OR TWO MAY BE
SEVERE.
- ELEVATED FIRE WEATHER CONDITIONS TODAY THRU FRIDAY; LOCALLY
CRITICAL FIRE WEATHER POSSIBLE THURSDAY.
- COOLER AND POTENTIALLY WETTER THIS WEEKEND INTO NEXT WEEK.
DISCUSSION
THROUGH TUESDAY...
OUR WEATHER OVER THE NEXT WEEK WILL BE DICTATED LARGELY BY THE
DIRTY UPPER LEVEL LOW SITTING TO OUR WEST OVER THE PNW. THE
ENERGY/VORTICITY WITH THIS FEATURE IS NOT NEATLY ORGANIZED AND
THUS THE LOCATION WILL WOBBLE SLIGHTLY OVER THE NEXT FEW DAYS
WHICH WILL SOMETIMES PUSH INTO OUR CWA, WHILE OTHER TIMES MAY
RETROGRADE SLIGHTLY. WHEN THE LOW IS FARTHER WEST MUCH OF THE CWA,
ESPECIALLY OUR EAST, WILL BE UNDER THE INFLUENCE OF THE RIDGE
IMPACTING THE CENTRAL GREAT PLAINS.
THE FIRST OF THESE PUSHES OF ENERGY WILL IMPACT PRIMARILY WESTERN
AND NORTHERN MONTANA LATER TODAY. WHILE MOST OF THE ENERGY WILL BE
CLOSER TOWARDS THE LOW IN NW MT AND WESTERN AB, A TRAILING AREA OF
F-GEN WILL SAG THROUGH OUR ENTIRE CWA. AHEAD OF THIS FRONT THERE
WILL BE SOME GUSTY WINDS IN THE FOOTHILLS OF SOUTH-CENTERAL
MONTANA, ESEPCAILLY IN GAP PRONE AREAS SUCH AS LIVINGSTON AN BIG
TIMBER. THIS WIND, COMBINED WITH THE LOW RH VALUES WILL PRODUCE
ELEVATED FIRE WEATHER CONCERNS, WITH AN EMPHASIS ON LOCATIONS
OUTSIDE OF THE HIGHER ELEVATIONS.
AS THE VORT MAX MOVES TO OUR NW AND THE FRONT PUSHES THROUGH OUR
AREA SHOWERS AND THUNDERSTORMS WILL INITIATE OFF OF THE MOUNTAINS AND
MOVE TOWARDS THE NE. THESE STORMS SHOULD REMAIN FAIRLY BENIGN TO
START BEFORE THEY GET INTO A MORE SUPPORTIVE ENVIRONMENT. WHILE
ANY STORM COULD PRODUCE GUSTY WINDS, THE SEVERE WIND GUSTS ARE
MOST LIKELY IN OUR NW ZONES NEAR HARLOWTON. SOUNDINGS HERE SHOW A
CLASSIC INVERTED-V TYPE ENVIRONMENT IN ADDITION TO 30 TO 40 KT
WINDS IN THE 700-500MB LAYER WHICH COULD BE FORCED DOWN IN
STRONGER CONVECTION. AS THE STORMS THAT INITIATED OFF OF THE
BIGHORNS MOVE TO THE NE THEY WILL ENCOUNTER A BETTER ENVIRONMENT
ONCE THEY GET THROUGH ROSEBUD CO. LOW LEVEL STRATUS THIS MORNING
WAS INDICATIVE OF GOOD MOISTURE ADVECTION OUT OF THE PLAINS INTO
FAR EASTERN MT AND NOW THE OBS ARE SHOWING THIS WITH DEW POINTS
AT KMLS IN THE MID 50S F AND AT KBHK IN THE LOW 60S F. THESE SE
WINDS AT THE SURFACE WILL REMAIN AS THE STORMS MOVE TOWARDS THE
AREA LATE THIS AFTERNOON INTO THE EVENING CREATING GOOD LOW LEVEL
SHEAR WITH VEERING WINDS THROUGH THE LOWEST 2KM AGL WITH 90
DEGREES OF DIRECTIONAL SHEER. ML CAPE AROUND 2000 J/KG NEAR BAKER
AT 23Z PER THE RAP COMBINED WITH A GOOD DISTRIBUTION OF THIS
ENERGY THROUGHOUT THE COLUMN SHOULD SUPPORT GOOD UPDRAFT GROWTH;
WHEN COMBINING THAT WITH 40KTS OF 0-8KM SHEAR THE UPDRAFTS SHOULD
BE ABLE TO SUPPORT SUPERCELL TYPE STORMS EASILY. ASIDE FROM THE
WINDS AND HEAVY RAIN THAT COME STANDARD WITH SUPERCELLS, THE MAIN
THREAT BEAR BAKER, MT WILL BE LARGE HAIL. WITH ~20KTS OF SPEED
SHEAR IN THE -10C TO -30C LAYER, THE TILT OF THE UPDRAFTS WIL BE
ABLE TO SUPPORT GOOD HYDROMETER SIZE SORTING; COMBINED WITH THE
WELL DISTRIBUTED CAPE, LARGE HAIL IS POSSIBLE. I WOULD NOT BE
SURPRISED TO SEE THE STRONGEST STORM OF THE EVENING EVEN DROP A
FEW GOLF BALL SIZED STONES.
LOOKING AT THURSDAY, THERE HAS BEEN A SLIGHT DECREASE IN OVERALL
DYNAMICS ACROSS THE REGION. 700MB WINDS PEAK IN THE MORNING HOURS
BEFORE WEAKENING TO 20-30KTS DURING PEAK DAYTIME HEATING HOURS.
WITH THE LACK OF DYNAMICS AND FORCING, WIDESPREAD PRECIPITATION
AND CLOUDS IS NOT EXPECTED WHICH WILL ALSO KEEP MIN RH VALUES LOW.
IT IS WORTH NOTING THOUGH THAT THE RH VALUES HAVE COME UP JUST A
FEW PERCENT IN OUR FAR WESTERN ZONES WITH THE LATEST MODEL RUNS.
THIS IS LIKELY DUE TO THE WEAKER DOWNSLOPE WINDS. ALL THAT BEING
SAID, THERE IS STILL A CHANCE FOR LOCALLY CRITICAL FIRE WEATHER
ACROSS THE WESTERN HALF OF OUR FORECAST AREA THURSDAY.
AS WE HEAD INTO THE WEEKEND THERE IS STILL SOME UNCERTAINTY
AROUND THE FORECAST. THERE IS BETTER AGREEMENT THAT THE PARENT
LOW WILL SLOWLY MOVE EASTWARDS STARTING FRIDAY PUTTING THE
WESTERN 1/3 OF THE CWA UNDER AN AREA OF CVA AND SW FLOW. THIS
COULD BRING DAILY CHANCES FOR SHOWERS AND STORMS FOR LOCATIONS
WEST OF BILLINGS IF IT VERIFIES. ADDITIONALLY, IT COULD ALSO BRING
PERIODS OF BREEZY CONDITIONS ACROSS THE REGION. ON FRIDAY THE
FORECAST WINDS HAVE COME UP A BIT FOR A LOT OF THE AREA. DUE TO
THE CVA AHEAD OF THE SHORTWAVE AS WELL AS WARM TEMPERATURES,
THERE WILL BE A SFC LOW THAT DEVELOPS ROUGHLY OVER BILLINGS WHICH
SHOULD HELP ENHANCE WINDS TO ITS EAST. THIS WOULD RESULT IN
ELEVATED FIRE WEATHER ACROSS OUR SOUTHERN AND EASTERN ZONES WHEN
YOU COMBINE HIGHS IN THE 90S AND MIN RH VALUES IN THE TEENS.
EARLY NEXT WEEK IT LOOKS LIKE ANOTHER TROUGH COULD DIG OFF OF THE
CA COAST WHICH WOULD HELP FINALLY PUSH OUR INITIAL SHORTWAVE
THROUGH AND OUT OF OUR AREA. THIS COULD RESULT IN A GOOD CHANCE OF
PRECIPITATION AND A NOTABLE COOLDOWN. THIS NEW TROUGH WOULD THEN
TAKE OVER AS OUR PRIMARY WEATHER MAKER. WMR
AVIATION
SOUTHWESTERLY WINDS OF 20 TO 30 KTS WILL BE COMMON FROM KBIL AND
AREAS WEST THIS AFTERNOON AND EVENING, WHILE SOUTHEASTERLY WINDS
OF 20 TO 30 KTS WILL BE FOUND NEAR THE DAKOTAS BORDER. EXPECT
WINDS TO DECREASE OVERNIGHT. A DISTURBANCE LIFTING THROUGH THE
REGION WILL BRING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
TO THE AREA THIS AFTERNOON AND EVENING. SOME OF THE STORMS COULD
BE STRONG TO SEVERE, PARTICULARLY FROM KMLS TO KBHK AND PRODUCE
LOCAL MVFR CONDITIONS. WIND GUSTS OF 40 TO 50 KTS AND LARGE HAIL
ARE POSSIBLE. MOST CONVECTIVE ACTIVITY WILL EXIT THE AREA BY 03Z.
STP
PRELIMINARY POINT TEMP/POPS
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 059/085 058/090 057/082 057/077 059/077 055/074 053/076
22/W 20/U 00/U 11/B 54/W 52/W 21/B
LVM 047/076 048/082 047/079 047/075 049/073 045/071 043/073
00/N 10/U 21/U 11/B 65/T 52/T 22/W
HDN 053/088 053/093 051/084 052/081 056/081 050/076 047/077
20/U 00/U 00/U 01/B 44/W 52/W 22/W
MLS 057/086 060/094 059/086 059/081 060/080 056/075 051/076
20/U 00/U 00/U 12/T 64/T 63/W 11/B
4BQ 060/089 063/097 060/088 060/083 062/084 058/078 053/078
20/U 00/U 00/U 02/T 53/T 42/W 21/B
BHK 056/089 058/098 061/091 056/084 055/082 052/078 046/078
50/U 00/U 00/U 13/T 65/T 53/W 11/U
SHR 052/086 053/093 054/085 053/079 054/080 050/075 046/075
00/U 00/U 00/U 02/W 44/W 42/W 11/U
BYZ WATCHES/WARNINGS/ADVISORIES
MT...RED FLAG WARNING IN EFFECT FROM NOON TO 9 PM MDT THURSDAY FOR
ZONES 123>129.
WY...RED FLAG WARNING IN EFFECT FROM NOON TO 9 PM MDT THURSDAY FOR
ZONE 284.
WEATHER.GOV/BILLINGS
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